JP2002148137A - Leakage inspection method for heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a leakage inspection method for a heat exchanger capable of realizing labor-saving equipment and reduction in labor and times. SOLUTION: This heat exchanger is provided with a pair of header pipes 1 and 2, a plurality of heat exchanging pipes 3 connected to the header pipes 1 and 2, a liquid receiver 10 communicated with one header pipe 1, and a heating medium flow passage reaching an outflow port 9 arranged in the other header pipe 2 from an inflow port 8 arranged in one header pipe 1 via the header pipes 1 and 2, the heat exchanging pipes 3, and the liquid receiver 10. In leakage inspection of the heat exchanger, an inspection gas (He gas) is charged from the outflow port 9 while the outflow port 9 is hermetically sealed and the liquid receiver 10 is sealed by means of a cap 16, a vacuum atmosphere is made while water-tightness and air-tightness of the cap 16 sealed part in the liquid receiver 10 is maintained, and leakage is detected on the basis of the inspection gas quantity leaking into the vacuum atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting a heat exchanger for leaks, and more particularly, to a method for inspecting a heat exchanger for leaks integrally provided with a receiver.

[0002]

2. Description of the Related Art In general, a pair of header pipes, a plurality of heat exchange pipes connected to the header pipes in parallel with each other, a receiver connected to one header pipe,
Heat with a receiver having a heat medium flow path from an inlet provided on one header pipe to an outlet provided on the other header pipe via a header pipe, a heat exchange pipe and a receiver. Exchangers are known.

In the heat exchanger, the main body of the header pipe, the heat exchange pipe and the liquid receiver, and the heat exchange fins interposed between adjacent heat exchange pipes are all made of an aluminum member such as an aluminum hollow extrusion. The main part (semi-finished product) is formed of a shape member or a bent plate made of aluminum or the like and integrally formed by brazing. After inserting, for example, a filter or a desiccant into the liquid receiver of the semi-finished product of the heat exchanger, the liquid receiver is sealed with a cap to obtain a finished product.

In the process of manufacturing the heat exchanger, it is necessary to perform a leak test to confirm the flow of the heat medium. Therefore, conventionally, first, a vacuum chamber is hermetically sealed with the outlet of the brazed semi-finished product and the receiver sealed, and in this state, an inspection gas is sealed from the inlet and leaked into the vacuum chamber. Perform a primary leak test to detect leaks based on the amount of gas used. Then, after coating, a filter and a desiccant etc. for removing dust and sludge in the heat medium condensed in the receiver are inserted, and sealed with a cap to obtain a finished product. The exchanger (finished product) is sealed in a vacuum chamber, and the same as the primary leak test described above, the test gas is sealed from the inlet and the leak is detected based on the amount of the test gas leaking into the vacuum chamber. A leak test was being performed. The reason for performing the leak inspection twice in this way is that after brazing, the baking is performed at a temperature of about 130 ° C. in the painting process, so that a filter or a desiccant cannot be inserted into the liquid receiver. After conducting a primary leak test to check for leaks of semi-finished products after brazing, insert a filter and desiccant into the receiver,
This is because, after sealing with a cap to obtain a finished product, a leak test must be performed again.

[0005]

However, in this kind of conventional heat exchanger leak inspection method, both the semi-finished heat exchanger and the finished heat exchanger are sealed in a vacuum chamber in the same manner as in the leak inspection. However, there is a problem that not only the equipment becomes large-scale, but also much labor and time are required for the leak inspection.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a method for inspecting a leak in a heat exchanger which can save labor and reduce labor and time. is there.

[0007]

Means for Solving the Problems To solve the above problems, the invention according to claim 1 comprises a pair of header pipes,
A plurality of heat exchange tubes connected to these header pipes,
A receiver connected to one header pipe and an inlet provided on one header pipe to an outlet provided on the other header pipe through the header pipe, the heat exchange pipe and the receiver. A leak inspection method for a heat exchanger including a heat medium flow path, wherein the outlet or the inlet is sealed, and the receiver is sealed with a cap, and inspection is performed from the inlet or the outlet. A gas is sealed, and at the same time, the cap sealing portion of the liquid receiver is maintained in a gas-water-tight manner to form a vacuum atmosphere, and leakage is detected based on an amount of the test gas leaking into the vacuum atmosphere.

According to the first aspect of the present invention, while the outflow port or the inflow port is sealed and the receiver is sealed with a cap, the test gas is sealed from the inflow port or the outflow port and the receiving gas is received. A vacuum atmosphere is maintained while keeping the sealing cap of the liquid container airtight, and the amount of the test gas leaking into the vacuum atmosphere can be used to detect leakage, so that the entire heat exchanger is sealed in a vacuum chamber. Without this, it is possible to inspect the receiver for leakage. Therefore, a large-scale facility is not required, and a leak test can be performed with a small amount of labor and in a short time.

According to a second aspect of the present invention, there is provided a pair of header pipes, a plurality of heat exchange tubes connected to the header pipes, and a liquid receiver connected to one of the header pipes.
Leakage of a heat exchanger including a heat medium flow path from an inlet provided on one header pipe to an outlet provided on the other header pipe via the header pipe, the heat exchange pipe, and the liquid receiver. An inspection method, wherein the heat exchanger with the outlet or the inlet and the receiver sealed is sealed in a vacuum chamber, and an inspection gas is sealed from the inlet or the outlet to leak into the vacuum chamber. A primary leak inspection step of detecting a leak based on the amount of the test gas to be inspected, and inserting a filter, a desiccant, etc. into the receiver of the heat exchanger taken out of the vacuum chamber through the primary leak inspection step. At the same time, in a state sealed with a cap, an inspection gas is sealed from the above-mentioned inlet or outlet, and a vacuum atmosphere is formed while keeping the cap sealing portion of the receiver air-tight, and leaks into this vacuum atmosphere. Do A secondary leakage inspection process for detecting a leak in an amount of 査用 gas, and having a.

[0010] According to the second aspect of the present invention, parts other than the liquid receiver are inspected by the primary leak inspection, and the leakage inspection of the liquid receiver is performed in the same manner as in the first aspect. With the inlet sealed and the receiver sealed with a cap, a test gas is sealed from the inlet or outlet, and a vacuum atmosphere is maintained while keeping the cap sealing part of the receiver airtight. Since the leak can be detected based on the amount of the test gas leaking into the vacuum atmosphere, the leak of the liquid receiver can be inspected without enclosing the entire heat exchanger in a vacuum chamber. Therefore, a large-scale facility is not required, and a leak test of the entire heat exchanger can be performed with a small amount of labor and in a short time.

According to a third aspect of the present invention, in the method for inspecting a leak of a heat exchanger according to the second aspect, before the secondary leak inspection step, the pressure detecting means is attached to the outlet or the inlet. The method includes a step of supplying gas from an inflow port or an outflow port and checking a gas ventilation state by a pressure detection unit.

According to the third aspect of the present invention, pressure is detected by supplying gas from the inflow port or the outflow port with the pressure detection means attached to the outflow port or the inflow port before the secondary leak inspection step. Since the gas ventilation state is confirmed by the means, it is possible to determine whether or not the heat exchanger to be subjected to the secondary leak test is appropriate as a product. Therefore, it is possible to improve the reliability of the secondary leak test for performing the leak test of only the sealed portion of the liquid receiver.

According to a fourth aspect of the present invention, in the method for inspecting a heat exchanger for leaks according to the first or second aspect, vacuum means is connected to the cap sealing portion of the liquid receiver via a coupler and a suction pipe. The amount of leakage of the inspection gas in the vacuum atmosphere is detected by a leakage detecting means connected to the suction pipe.

According to the fourth aspect of the present invention, the vacuum means is connected to the cap sealing portion of the receiver via the coupler and the suction pipe, and the leak detecting means connected to the suction pipe is used for the vacuum atmosphere. Since the amount of leakage of the inspection gas is detected, the leakage of the liquid receiver can be reliably inspected, and the reliability of the inspection can be improved.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a heat exchanger according to an embodiment of the present invention;

FIG. 1 is a schematic sectional view showing an example of a heat exchanger which is an object to be inspected by the heat exchanger leakage inspection method of the present invention, and FIG. 2 is a leak inspection of the heat exchanger of the present invention. 5 is a flowchart of a method.

The heat exchanger 20 includes a pair of header pipes 1 and 2 having caps 1a and 2a closed at upper and lower ends, respectively, and a plurality of parallel heat exchange tubes 3 connected to the header pipes 1 and 2. , A corrugated fin 4 interposed between adjacent heat exchange tubes 3, and an upper side plate 5 a erected at the upper and lower ends of both header pipes 1, 2.
The main part is composed of a heat exchanger main body 21 having a lower side plate 5b and a liquid receiver 10 connected to one header pipe 1 via an inflow path 6 and an outflow path 7.

In this case, one header pipe 1 (FIG. 1)
, A heat medium inlet 8 is provided on the upper side of the left header pipe). An outlet 9 for the heat medium is provided on the lower side of the other header pipe 2 (the right header pipe in FIG. 1). Partition plates 11 are provided inside the header pipes 1 and 2, and the partition plates 11 allow the heat medium flowing from the inlet 8 to cool while flowing through the upper heat exchange pipe 3. Then, the heat medium from which the dust, sludge and the like in the heat medium have been removed by the filter 12 built in the liquid receiver 10 while flowing into the liquid receiver 10 and gas-liquid separated in the liquid receiver 10 is further added. It is cooled and discharged from the outlet 9.

The heat exchanger 20 configured as described above is
The header pipes 1 and 2, the heat exchange tube 3, and the corrugated fins 4 constituting the heat exchanger body 21 are all formed of aluminum members, for example, aluminum hollow extruded members or aluminum bent plate members. Liquid receiver 10
Body 15 is also formed of, for example, an aluminum hollow extruded profile or an aluminum electric resistance welded tube. Then, in a state where the header pipes 1 and 2, the heat exchange pipe 3, the corrugated fins 4, the liquid receiver main body 15 and the like are assembled, they are placed in a furnace and heated at a temperature of, for example, about 600 ° C. and brazed integrally. . Further, after inserting a frame 13 made of, for example, plastic into which the filter 12 and a desiccant (not shown) are incorporated, the cap 16 is sealed in the lower end opening of the receiver 15. Thus, the heat exchanger 20 with a liquid receiver is completed. Since the heat exchanger 20 with a liquid receiver is mounted on a vehicle such as an automobile, for example, a flat surface 14 for mounting, which will be described later, is provided on a part of the liquid receiver main body 15, for example, on one side of an outer peripheral surface. Have been.

The heat exchanger with a liquid receiver 20 configured as described above is commercialized through the steps shown in FIG. 2 in the manufacturing process. That is, first, the header pipes 1, 2,
The heat exchange tube 3, the corrugated fin 4, the receiver main body 15 and the like are assembled and welded to temporarily assemble (step 2-1). Next, the temporarily assembled product is placed in a furnace, and is heated at a temperature of about 600 ° C. and brazed (Step 2-2). Straightening the brazed semi-finished product (heat exchanger body 21) (Step 2)
-3) Then, it is checked whether or not there is a leak in the heat medium flow path of the heat exchanger body 21 (primary leak test: Step 2).
4). The heat exchanger body 21 that has passed the primary leak test has its surface coated (step 2-5), and then has the filter 12 and a desiccant (not shown) built in the receiver body 15. For example, a plastic frame 13 is inserted and sealed with a cap 16 (step 2-6). The ventilation of the heat medium flow path of the heat exchanger 20 thus completed is confirmed (step 2-7), and thereafter, the heat medium flow of the heat exchanger 20 in which the ventilation of the heat medium flow path is confirmed Inspect the road for leaks (secondary leak inspection: Step 2-
8). The heat exchanger 20 that has passed the secondary leak inspection is stored in a warehouse to be shipped as a finished product (Step 2-).
9).

In this case, to perform the above-mentioned primary leak inspection,
As shown in FIG. 3, the outlet 9 of the heat exchanger body 21 is
8 and with the lower end opening of the receiver main body 15 sealed with the temporary cap 29, it is put into the vacuum chamber 200, and the gas supply port 201 and the inflow port 8 provided in the vacuum chamber 200 are connected to the hose 202. And gas supply port 2
01 and a supply source 203 of an inspection gas, for example, a helium (He) gas, are connected by a gas supply pipe 204. The gas supply pipe 204 is provided with an on-off valve 205. Also,
A gas leak inspection window hole 206 is provided in the vacuum chamber 200, and a gas detector 207 sensitive to He gas, which is leak detection means, is connected to the gas leak inspection window hole 206.

As described above, with the outlet 9 of the heat exchanger body 21 and the lower end opening of the receiver body 15 sealed with the stopper 28 and the temporary cap 29, the release valve 205 is opened and H
The e gas can be sealed in the heat medium flow path, and the amount of He gas leaking into the vacuum chamber 200 can be measured to check for leakage. That is, when a predetermined amount or more of He gas is confirmed in the vacuum chamber 200, it is determined that there is a leak in the heat medium flow path,
When the amount is less than the predetermined amount, there is no leakage and the test is passed.

In order to check the ventilation of the heat medium flow path, the plug 28 of the outlet 9 of the heat exchanger 20 taken out of the vacuum chamber 200 is removed, and the pressure detecting means which is a pressure detecting means is used instead. A vessel 300 is attached, and a compressed air supply source 302 is connected to the inlet 8 via a compressed air supply pipe 301. The compressed air supply pipe 301 is provided with an on-off valve 303. In this state, the open / close valve 303 is opened to supply the dried compressed air from the compressed air supply source 302 into the heat medium flow path, and the pressure detector 300 checks whether the ventilation state is good. In this case, for example, the supply pressure of the compressed air is set to 0.8 MPa, and the set value (0.75 MPa) is set.
The arrival time was measured and the set value (0.75M
The heat exchanger 20 that does not reach Pa) is regarded as defective, and the one that reaches the set value (0.75 MPa) within 2 seconds is regarded as acceptable (see FIG. 5).

As described above, by attaching the pressure detector 300 to the outlet 9 and confirming the ventilation of the heat medium flow path,
The ventilation can be confirmed more reliably than the conventional confirmation method in which the worker puts his hand on the outlet 9 to confirm the ventilation.

The heat exchanger 20 that has been accepted as a result of the ventilation check of the heat medium flow path as described above is then subjected to a secondary leak test. In this secondary leak test, as shown in FIG. 6, a vacuum pump 22 which is a vacuum means is connected to the cap sealing portion of the liquid receiver 10 via a coupler 30 and a suction pipe 23, and is connected to the suction pipe 23. The detection can be performed by detecting the amount of leakage of the inspection gas in the vacuum atmosphere by the gas detector 24 sensitive to He gas, which is a leak detection means to be performed.

That is, the coupler 30 is connected to the receiver main body 15.
The coupler 30 is connected to the lower end of the
2 and a gas detector 24 is interposed in the middle of a suction pipe 23 connecting the coupler 30 and the vacuum pump 22, so that the leakage of the heat medium flowing portion in the sealed portion of the liquid receiver 10 with the cap 16 is performed. Can be inspected. That is, when the gas detector 24 confirms that the He gas is equal to or more than a predetermined amount, it is determined that there is a leak in the sealed portion of the liquid receiver 10 with the cap 16, and when the He gas is equal to or less than the predetermined amount, there is no leak and the test is passed. .

In this case, as shown in FIGS. 7 to 10, the coupler 30 has an outer cylindrical case 40 having an open cylindrical portion 41 at one end surrounding the lower end of the liquid receiver main body 15, and an outer cylindrical case 40. A coupler body 50 mounted on the other end of the outer cylinder case 40 and having a supply port 51 for supplying a pressurized fluid, for example, compressed air, into the outer cylinder case 40;
The inner tube 60 is slidably inserted into the inner tube 60, and the base end is connected to the suction tube 23 as the other connected tube. It mainly comprises an elastically deformable ring-shaped collet 70 and a seal packing 80 interposed therebetween.

In this case, the outer cylinder case 40 is
A tubular base 42 having a diameter larger than that of the opening tubular portion 41 is provided on the base end side of the first cylindrical portion. In addition, a first inner peripheral surface 43 having a larger diameter than the inner peripheral surface 41 a of the opening cylindrical portion 41 is provided on the inner periphery of the cylindrical base portion 42.
A second inner peripheral surface 44 having a larger diameter than the first inner peripheral surface 43;
A third inner peripheral surface 45 having a diameter larger than that of the second inner peripheral surface 44 is provided, and a female screw portion 46 engraved on the third inner peripheral surface 45 is provided with a mounting cylindrical portion 52 of the coupler body 50. The outer cylinder case 40 and the coupler body 50 are connected in a state where the male screw portion 53 engraved on the outer cylinder is screwed. In this case, the second inner peripheral surface 44 and the inner peripheral surface 52a of the mounting tubular portion 52 are configured to have the same diameter.

The inner cylinder 60 is provided at a base end of the hollow piston 61 and a hollow piston 61 that is slidably inserted into the inner peripheral surface 41a of the opening cylinder 41 of the outer cylinder case 40. 2, an outward flange 62 slidably fitted into the inner peripheral surface 44, and a through hole 5 connected to the base end of the outward flange 62 and provided at the center of the coupler body 50.
4 and a connecting pipe 63 slidably fitted into the connecting pipe. In this case, the connecting pipe portion 63 is formed to have a smaller diameter than the hollow portion 61a of the hollow piston portion 61, and is hollow through a communication hole 62a having the same diameter as the inner diameter of the connecting pipe portion 63 provided in the outward flange portion 62. The hollow part 61a of the piston part 61 and the connection pipe part 63 are connected. In addition, outer cylinder case 4
A compression coil spring 48 is compressed between a step 47 on the side of the opening cylinder 41 of the first inner peripheral surface 43 provided on the first cylindrical base 42 and the outward flange 62 of the inner cylinder 60. The inner cylinder 60 is constantly pressed toward the base end by the elastic force of the compression coil spring 48. The outer peripheral surface of the hollow piston portion 61, the outward flange portion 6
2 and the outer circumferential surface of the connecting pipe portion 63 are provided with circumferential grooves 64a, 64b, 64c, respectively.
O-rings 65a, 6a are provided in 4a, 64b, 64c, respectively.
5b and 65c are fitted.

On the other hand, as shown in FIG. 7B, the collet 70 has a flat pressing surface 71 and the pressing surface 7.
1, tapered surfaces 72a, 7 narrower outward from both sides.
It is formed of a ring-shaped elastically deformable member having 2b, for example, a member made of polyacetal resin (POM).
The collet 70 formed in this way is the outer cylinder case 40
The one tapered surface 72a is engaged with the inclined guide surface 90a provided on the distal opening 41b of the opening cylindrical portion 41, and the other tapered surface is provided. The face 72b is provided with a collet 70 and a seal packing 80.
Are engaged with the inclined guide surface 90b provided on the collar 100 interposed therebetween.

To perform a secondary leak test on the heat exchanger 20 with a liquid receiver using the coupler 30 configured as described above,
The suction pipe 23 is connected to the connection pipe 63 in advance, and the compressed air supply source 26 is connected to the supply port 51 via the compressed air supply pipe 25 in advance. Then, the opening cylindrical portion 4 of the coupler 30
1 is mounted so as to surround the lower end of the receiver main body 15 (see FIGS. 7 and 9). In this state, the compressed air supply pipe 25
The open / close valve 27 interposed in the compressed air supply source 26 is opened.
When the compressed air is supplied into the chamber 55 between the outward flange portion 62 of the inner cylinder 60 and the coupler body 50 from the inside, the inner cylinder 60 is pressed against the elastic force of the compression coil spring 48 by the pressurization of the compressed air. Move to the tip side. As the inner cylinder 60 moves, the collar 100 and the seal packing 80 are also pressed toward the distal end, so that the tapered surfaces 72 a and 72 b of the collet 70 are formed on the inclined guide surface 9 provided on the open cylindrical portion 41 of the outer cylindrical case 40.
0a and an inclined guide surface 90b provided on the collar 100
And the pressing surface portion 7 of the collet 70
1 bulges toward the inner side, that is, the outer peripheral surface side of the liquid receiver main body 15, and comes into close contact with the outer peripheral circular surface of the liquid receiver main body 15 (see FIG. 10). Further, as the inner cylinder 60 moves toward the distal end, the seal packing 80 is compressed and deformed, and
1 is in close contact with the entire outer periphery of the opening and the entire inner periphery of the opening cylindrical portion 41 (FIG. 1).
2).

Therefore, in the coupler 30, the collet 70 is firmly pressed against the outer circular surface of the non-circular receiver main body 15 having the flat surface 14, and the seal packing 80 is air-tightly sealed on the entire outer peripheral surface of the receiver main body 15. , And is connected to the receiver main body 15 firmly and in a state of maintaining airtightness.

Thus, the coupler 30 is connected to the receiver main body 1.
5, He gas is passed from the inlet 8 to the heat exchanger 20 while the outlet 9 is sealed with a stopper as in the primary leak test.
And pressurized. Then, in this state, the vacuum pump 2
2 and the opening / closing valve 22a of the vacuum pump 22 is opened to evacuate the cap 16 mounting portion of the liquid receiver 10, while the gas detector 24 separates the liquid from the liquid receiver 10 to He.
It can be checked whether gas leaks.

By performing the secondary leak inspection as described above, it is possible to inspect the leak from the sealed portion by the cap 16 of the receiver 10 without enclosing the entire heat exchanger 20 in the vacuum chamber 300. Can be. Therefore, a large-scale facility is not required, and a leak test can be performed with a small amount of labor and in a short time.

In the above embodiment, at the time of the primary leak inspection, the outlet 9 is sealed with the stopper 8 and the He 8 is injected from the inlet 8 side.
Gas is sealed, and at the time of heat medium flow path ventilation check inspection,
Although the case where the pressure detector 300 is attached to the outlet 9 and compressed air is supplied from the inlet 8 has been described, the outlet 9 and the inlet 8 may be reversed. That is, at the time of the primary leak inspection, the inflow port 8 is sealed with the stopper 8 and He gas is sealed from the outflow port 9 side, and at the time of the heat medium flow path ventilation check inspection, the pressure detector 300 is attached to the inflow port 8. Thus, compressed air may be supplied from the outlet 9 side.

[0036]

As described above, according to the present invention, because of the above-described configuration, the following excellent effects can be obtained.

(1) According to the first aspect of the present invention, while the outflow port or the inflow port is closed and the receiver is sealed with a cap, the inspection gas is sealed from the inflow port or the outflow port. At the same time, a vacuum atmosphere is maintained while keeping the cap closed part of the receiver airtight, and the amount of the test gas leaking into the vacuum atmosphere can be used to detect a leak. The leakage of the receiver can be inspected without enclosing the receiver. Therefore, a large-scale facility is not required, and a leak test can be performed with a small amount of labor and in a short time.

(2) According to the second aspect of the invention, parts other than the liquid receiver are inspected by the primary leak inspection, and the leakage inspection of the liquid receiver is performed in the same manner as in the first aspect of the invention. With the outlet or inlet sealed and the receiver sealed with a cap, test gas is sealed from the inlet or outlet, and vacuum is maintained while keeping the cap closed part of the receiver airtight. Since the leak can be detected based on the amount of the test gas leaking into the vacuum atmosphere, the leak of the liquid receiver can be inspected without enclosing the entire heat exchanger in a vacuum chamber. . Therefore, a large-scale facility is not required, and a leak test of the entire heat exchanger can be performed with a small amount of labor and in a short time.

(3) According to the third aspect of the invention, before the secondary leak inspection step, gas is supplied from the inflow port or the outflow port with the pressure detection means attached to the outflow port or the inflow port. Pressure detection means to check the gas ventilation state.
It is possible to determine whether the heat exchanger to be subjected to the secondary leak test is appropriate as a product. Therefore, it is possible to improve the reliability of the secondary leak test for performing the leak test of only the sealed portion of the liquid receiver.

(4) According to the fourth aspect of the present invention, the vacuum means is connected to the cap sealing portion of the receiver via the coupler and the suction pipe, and the leak detecting means is connected to the suction pipe. Since the amount of leakage of the test gas in the vacuum atmosphere is detected, the leakage of the receiver can be reliably tested, and the reliability of the test can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an example of a heat exchanger which is an object to be inspected by a heat exchanger leak inspection method of the present invention.

FIG. 2 is a flowchart of a method for inspecting a heat exchanger for leakage according to the present invention.

FIG. 3 is a schematic sectional view showing a primary leak test according to the present invention.

FIG. 4 is a schematic cross-sectional view showing a test for confirming the ventilation of a heat medium flow channel according to the present invention.

FIG. 5 is a graph showing the relationship between heat medium flow path pressure and time in the air flow check of the heat medium flow path.

FIG. 6 is a schematic sectional view showing a secondary leak test according to the present invention.

7A is a cross-sectional view showing a state before coupling of a coupler used for a secondary leak test according to the present invention, and FIG.
It is an enlarged view (b) of the I section of (a).

FIG. 8 is a sectional view showing a connected state of the coupler.

FIG. 9 is a cross-sectional view taken along the line II-II of FIG.

FIG. 10 is a sectional view taken along the line III-III in FIG. 8;

FIG. 11 is a cross-sectional view taken along the line IV-IV in FIG.

FIG. 12 is a sectional view taken along the line VV in FIG. 8;

[Explanation of symbols]

 1, 2 Header pipe 3 Heat exchange tube 8 Inlet 9 Outlet 10 Liquid receiver 15 Liquid receiver main body 16 Cap 22 Vacuum pump 23 Suction tube 24 Gas detector (leakage detecting means) 28 Plug 29 Temporary cap 200 Vacuum chamber 203 He gas supply source 207 Gas detector (leakage detection means) 300 Pressure detector 302 Compressed air supply source

Claims (4)

[Claims] 1. A pair of header pipes, a plurality of heat exchange pipes connected to these header pipes, a liquid receiver connected to one header pipe, and an inlet provided in one header pipe. A method for inspecting a heat exchanger for leaks, comprising: a header pipe, a heat exchange pipe, and a heat medium flow path that leads to an outlet provided in the other header pipe via a liquid receiver. While sealing the receiver with a cap, sealing the test gas from the inlet or the outlet, and keeping the cap sealing portion of the receiver air-tight while maintaining a vacuum atmosphere. A method for inspecting a leak of a heat exchanger, wherein a leak is detected based on an amount of the inspection gas leaking into the vacuum atmosphere. 2. A pair of header pipes, a plurality of heat exchange pipes connected to these header pipes, a receiver connected to one header pipe, and an inlet provided in one header pipe. A method for inspecting a heat exchanger for leaks, comprising: a header pipe, a heat exchange pipe, and a heat medium flow path that leads to an outlet provided in the other header pipe via a liquid receiver. In addition, the heat exchanger in a state where the liquid receiver is sealed is sealed in a vacuum chamber, and a test gas is sealed from an inlet or an outlet to detect a leak based on an amount of the test gas leaking into the vacuum chamber. In the primary leak inspection step, while inserting a filter and a desiccant etc. in the receiver of the heat exchanger taken out of the vacuum chamber through the primary leak inspection step, while sealing with a cap, Inflow Alternatively, a test gas is sealed from the outlet, and a vacuum atmosphere is created while keeping the cap sealing portion of the receiver airtight, and a leak is detected by an amount of the test gas leaking into the vacuum atmosphere. A leak inspection method for a heat exchanger, comprising: a leak inspection step. 3. The leak inspection method for a heat exchanger according to claim 2, wherein the pressure detection means is attached to the outlet or the inlet before the secondary leak inspection step. A method for inspecting a leak of a heat exchanger, comprising a step of supplying a gas and confirming a ventilation state of the gas by a pressure detecting means. 4. The method according to claim 1, wherein a vacuum means is connected to the cap sealing portion of the receiver via a coupler and a suction pipe, and the cap is connected to the suction pipe. A method for detecting a leak of a test gas in a vacuum atmosphere by a leak detecting means.